Syntheses and crystal structures of two copper(I)-halide π,σ-coordination compounds based on 2-[(prop-2-en-1-yl)sulfan-yl]pyridine.

The title compounds, di-μ-chlorido-bis-({2-[(η-2,3)-(prop-2-en-1-yl)sulfan-yl]pyridine-κ}copper(I)), [CuCl(CHNS)], and di-μ-bromido-bis-({2-[(η-2,3)-(prop-2-en-1-yl)sulfan-yl]pyridine-κ}copper(I)), [CuBr(CHNS)], were obtained by alternating-current electrochemical synthesis starting from an ethano-lic solution of 2-[(prop-2-en-1-yl)sulfan-yl]pyridine () and the copper(II) halide. The isostructural crystals are built up from centrosymmetric [Cu ()] dimers, which are formed due to the π,σ-chelating behavior of the organic ligand. In the crystals, the dimers are linked by C-H⋯ hydrogen bonds as well as by aromatic π-π stacking inter-actions into a three-dimensional network.

Synthesis, structure and computational study of 5-[(prop-2-en-1-yl)sulfanyl]-1,3,4-thiadiazol-2-amine (Pesta) and its heterometallic π,σ-complex [CuFeCl(Pesta)][FeCl].

Copper(I) π-coordination compounds with allyl derivatives of azoles are an interesting subject of current research, but Cu π-complexes with other transition-metal ions incorporated in the structure have been virtually uninvestigated. The present work is directed toward the synthesis and structural characterization of the novel heterometallic Cu/Fe π-complex di-μ-chlorido-1:2κCl;2:3κCl-tetrakis[μ-5-(prop-2-en-1-ylsulfanyl)-1,3,4-thiadiazol-2-amine]-1:2κN:N;1(η),κN:2κN;2:3κN:N;2κN:3(η),κN-dicopper(I)iron(II) tetrachloridoferrate(II), [CuFeCl(CHNS)][FeCl] (1). The structure of the 5-[(prop-2-en-1-yl)sulfanyl]-1,3,4-thiadiazol-2-amine (Pesta, CHNS) ligand is also presented.

Synthesis and Structure of [Cu(Hapn)]NO3]NO3, [Cu(Hapn)(H2O)2]SiF6, [Cu(Hapn)(H2O)BF4]BF4 · H2O and [Cu(Hapn)(NH2SO3)2] π-complexes (apn = 3-(prop-2-en-1-ylamino)propanenitrile).

Four copper(I) π-complexes: [Cu(Hapn)NO3]NO3 (1), [Cu(Hapn)(H2O)2]SiF6 (2), [Cu(Hapn)(H2O)BF4]BF4·H2O (3) and [Cu(Hapn)(NH2SO3)2] (4) were prepared using alternating-current electrochemical technique, starting from alcohol solutions of 3-(prop-2-en-1-ylamino)propanenitrile (apn) titrated with appropriate acid and copper(II) salts (Cu(NO3)2 · 3H2O, CuSiF6 · 4H2O, Cu(BF4)2 · 6H2O or Cu(NH2SO3)2 · xH2O, respectively). Obtained compounds were characterized by single-crystal X-ray diffraction and partially by IR spectroscopy. In the structures of complexes 1, 2 and 4 Cu(I) cation possesses a tetrahedral environment formed by the C=C bond of one organic cation Hapn, the N atom of cyano group from another Hapn moiety, and two O atoms (from NO3- anions in 1, from H2O molecules in 2) or N atoms (NH2SO3- anions in 4).

Ligand-forced dimerization of copper(I)-olefin complexes bearing a 1,3,4-thiadiazole core.

As an important class of heterocyclic compounds, 1,3,4-thiadiazoles have a broad range of potential applications in medicine, agriculture and materials chemistry, and were found to be excellent precursors for the crystal engineering of organometallic materials. The coordinating behaviour of allyl derivatives of 1,3,4-thiadiazoles with respect to transition metal ions has been little studied. Five new crystalline copper(I) π-complexes have been obtained by means of an alternating current electrochemical technique and have been characterized by single-crystal X-ray diffraction and IR spectroscopy.

Two Related Copper(I) π-Complexes Based on 2-Allyl-5-(2-pyridyl)-2H-tetrazole Ligand: Synthesis and Structure of [Cu(2-apyt)NO3] and [Cu(2-apyt)(H2O)](BF4) Compounds.

By means of the alternating current electrochemical technique two new π-compounds [Cu(2-apyt)NO3] (1) and [Cu(2-apyt)(H2O)](BF4) (2) have been obtained starting from the mixture of 1-allyl-5-(2-pyridyl)-2H-tetrazole (1-apyt), 2-allyl-5-(2-pyridyl)-2H-tetrazole (2-apyt) and corresponding copper(II) salts, and have been structurally studied. Selective complexation towards 2-allyl- isomer results in a formation of 2-apyt complexes. Copper(I) ion in both 1 and 2 complexes coordinates the allylic C=C bond, one pyridyl and one tetrazole N atoms.

First N-allyl-aminothiadiazole copper(I) π-complexes: synthesis and structural peculiarities of [Cu(L)CF3SO3] and [Cu2(L)2(H2O)2](SiF6) · 2.5H2O compounds (L = 2-(allyl)-amino-5-methyl-1,3,4-thiadiazole).

By means of alternating current electrochemical technique two crystalline copper(I) π-complexes with fluorine containing anions [Cu(L)CF3SO3] (1) and [Cu2(L)2(H2O)2](SiF6)2 · 2.5H2O (2) (L - 2-(allyl)-amino-5-methyl-1,3,4-thiadiazole) have been obtained and characterized by X-ray single crystal diffraction and Raman spectroscopy. In both structures the organic molecule L acts as chelate-bridging tridentate ligand being connected to copper(I) by two N atoms of thiadiazole ring and C=C bond from allyl group resulting in a formation of stable cationic dimers [Cu(L)2]2+.

Synthesis and Crystal Structure of Copper(I) Nitrate π-complex with 1-allylbenzotriazole of Equimolar Composition.

The CuNO3 • C6H4N3(C3H5) compound (I) was obtained by alternating current electrochemical synthesis, starting from an ethanol solution containing Cu(NO3)2 • 3H2O and a mixture of 1- and 2-allylbenzotriazole titrated by HNO3 to pH = 4. The C=C bond of one 1-allylbenzotriazole molecule, the nitrogen atom from another ligand moiety, and two oxygen atoms from two nitrate-anions form a trigonal-pyramidal environment of the metal atom. The bridging function of the ligand moiety results in infinite metal-organic chains, interconnected by weak CH…O hydrogen bonds, π-π and π-σ stacking and van der Waals interactions.

Bis[bis-(3,5-diamino-1H-1,2,4-triazol-4-ium)copper(I)] tris-(hexa-fluoridosilicate).

In the title compound, [Cu(C(2)H(6)N(5))(2)](2)(SiF(6))(3), the asymmetric unit is composed of one [Cu(HL)(2)](3+) cation (where L is 3,5-diamino-1,2,4-triazole) and one and a half SiF(6) (2-) anions. The rather large positively charged guanazole ligand moiety promotes the low metal coordination number of 2 for the Cu(I) atom. The compound was obtained using the electrochemical alternating-current technique starting from an ethanol-methanol solution of CuSiF(6)·4H(2)O and guanazole.

Bis(diallyl-benzimidazolium) tetra-bromidocuprate(II).

The structure of the title ionic copper(II) compound, (C(13)H(15)N(2))(2)[CuBr(4)], is built up of isolated 1,3-diallyl-benzimidazolium cations and [CuBr(4)](2-) anions which are inter-connected by electrostatic inter-actions. Differences in packing of the heterocyclic cores results in a different structure compared with earlier investigated chloride and bromide analogues.

catena-Poly[[cyclo-tetra-mu-chlorotetracopper(I)]-bis{mu-3-[(2-morpholino-4-oxo-4,5-dihydro-1,3-thiazol-5-ylidene)methylphenoxy]propene}-2kappaN,1'eta2;1eta2,2'kappaN].

Crystals of a new copper(I) complex of composition [Cu4Cl4(C17H18N2O3S)2]n have been obtained by alternating-current electrochemical synthesis. In the crystal structure, the Cu and Cl atoms form a chair-like Cu4Cl4 cyclic fragment. The organic ligand acts as a bridge, being connected via the C=C bond of the allyl group to a Cu atom from one inorganic cycle and via the N atom of the thiazole ring to a Cu atom of another copper-chloride fragment.

catena-Poly[bis[(eta2-1-allyl-3-aminopyridinium)copper(I)]-di-mu-chloro-copper(I)-di-mu-chloro-copper(I)-di-mu-chloro].

Crystals of the title pi-complex, [Cu4Cl6(C8H11N2)2]n, were obtained by means of alternating-current electrochemical synthesis. The structure consists of infinite copper-chlorine chains to which 1-allyl-3-aminopyridinium moieties are attached via a eta2 Cu-(C=C) interaction. The two independent Cu atoms have distinct coordination environments.

Influence of Cl/Br substitution on the stereochemical peculiarities of copper(I) pi-complexes with the 1-allyl-2-aminopyridinium cation.

By using alternating-current electrochemical synthesis, crystals of the Cu(I) pi-complexes bis(1-allyl-2-aminopyridinium) di-micro-chloro-bis[chlorocopper(I)], (C(8)H(11)N(2))(2)[Cu(2)Cl(4)] or [H(2)NC(5)H(4)NC(3)H(5)][CuCl(2)], and bis(1-allyl-2-aminopyridinium) di-micro-(chloro/bromo)-bis[(chloro/bromo)copper(I)], (C(8)H(11)N(2))(2)[Cu(2)Br(2.2)Cl(1.8)] or [H(2)NC(5)H(4)NC(3)H(5)][CuBr(1.